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		Libreboot documentation: using diff and patch
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	<div class="section">
		<h1 id="pagetop">Diff and patch</h1>
			<p>This is just a quick guide for reference, use 'man' to know more.</p>
			<p>
				<a href="index.html">Back to index</a>
			</p>
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	<div class="section">

		<h1>
			Apply a patch
		</h1>

			<p class="important">
				To apply a patch to a single file, do that in it's directory:<br/>
				<b>$ patch &lt; foo.patch</b>
			</p>

			<p>
				Assuming that the patch is distributed in unified format identifying
				the file the patch should be applied to, the above will work. Otherwise:<br/>
				<b>$ patch foo.txt &lt; bar.patch</b>
			</p>

			<p>
				You can apply a patch to an entire directory, but note the &quot;p level&quot;.
				What this means is that inside patch files will be the files that you
				intend to patch, identified by path names that might be different
				when the files ane located on your own computer instead of on the computer
				where the patch was created. 'p' level instructs the 'patch' utility to
				ignore parts of the path name to identify the files correctly. Usually a
				p level of 1 will work, so you would use:<br/>
				<b>$ patch -p1 &lt; baz.patch</b>
			</p>

			<p>
				Change to the top level directory before running this. If a patch level
				of 1 cannot identify the files to patch, then inspect the patch file for file names.
				For example:<br/>
				<b>/home/user/do/not/panic/yet.c</b>
			</p>

			<p>
				and you are working in a directory that contains panic/yet.c, use:<br/>
				<b>$ patch -p5 &lt; baz.patch</b>
			</p>

			<p>
				You usually count one up for each path separator (forward slash)
				removed from the beginning of the path, until you are left with a path
				that exists in the current working directory. The count is the p level.
			</p>

			<p>
				Removing a patch using the -R flag<br/>
				<b>$ patch -p5 -R &lt; baz.patch</b>
			</p>

			<p><a href="#pagetop">Back to top of page.</a></p>
			
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	<div class="section">

		<h1>
			Create a patch with diff
		</h1>

			<p>
				Diff can create a patch for a single file:<br/>
				<b>$ diff -u original.c new.c &gt; original.patch</b>
			</p>

			<p>
				For diff'ing a source tree:<br/>
				<b>$ cp -R original new</b>
			</p>

			<p>
				Do whatever you want in new/ and then diff it:<br/>
				<b>$ diff -rupN original/ new/ &gt; original.patch</b>
			</p>

			<p><a href="#pagetop">Back to top of page.</a></p>
			
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	<div class="section">

		<h1>
			git diff
		</h1>

			<p>
				git is something special.
			</p>
			<p>
				Note: this won't show new files created.
			</p>

			<p>
				Just make whatever changes you want to a git clone and then:<br/>
				<b>$ git diff &gt; patch.git</b>
			</p>

			<p>
				Note the git revision that you did this with:<br/>
				<b>$ git log</b>
			</p>
			
			<p>
				Alternatively (better yet), commit your changes and then use:<br/>
				$ <b>git format-patch -N</b><br/>
				Replace N with the number of commits that you want to show.
			</p>

			<p><a href="#pagetop">Back to top of page.</a></p>
			
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	<div class="section">

		<h1>
			git apply
		</h1>

			<p>it really is.</p>

			<p>
				Now to apply that patch in the future, just git clone it again and do
				with the git revision you found from above:<br/>
				<b>$ git reset --hard REVISIONNUMBER</b>
			</p>

			<p>
				Now put patch.git in the git clone directory and do:<br/>
				<b>$ git apply patch.git</b>
			</p>
			
			<p>
				If you use a patch from git format-patch, then use <b>git am patch.git</b> instead of <b>git apply patch.git</b>. git-am
				will re-create the commits aswell, instead of just applying the patch.
			</p>

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	<div class="section">

		<p>
			Copyright &copy;  2014, 2015 Francis Rowe &lt;info@gluglug.org.uk&gt;<br/>
			Permission is granted to copy, distribute and/or modify this document
			under the terms of the GNU Free Documentation License, Version 1.3
			or any later version published by the Free Software Foundation;
			with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
			A copy of the license can be found at <a href="../gfdl-1.3.txt">../gfdl-1.3.txt</a>
		</p>

		<p>
			Updated versions of the license (when available) can be found at
			<a href="https://www.gnu.org/licenses/licenses.html">https://www.gnu.org/licenses/licenses.html</a>
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